1. Field of the Disclosure
The present invention relates in general to disk drives and, in particular, to a system, method and apparatus for an anticorrosion overcoat for magnetic media disks.
2. Description of the Related Art
Magnetic media disks in hard disk drives typically utilize an overcoat to protect them from corrosion. Currently, materials such as amorphous diamond-like carbon (DLC) and carbon-based materials such as CNx are used to provide ultrathin overcoats (e.g., less than 30 Å). However, amorphous silicon-based materials such as SiN, TiSiN, SiC and SiCN are prospective candidates to replace conventional overcoat materials. At reduced thicknesses, such Si materials exhibit better anticorrosion performances than carbon materials.
Unfortunately, the surfaces of Si materials are chemically unstable in humidity. This problem impairs their use as ultrathin disk overcoats. For example, when such overcoats are exposed to water vapor from ambient air, a hydrolysis reaction takes place on the surface of Si-based materials. This results in the growth of a thin film of silicon oxide (SiOx) at the film-air interface. SiOx formation on Si-based overcoat surfaces causes hard disk drive failures such as head crashes and irreversible disk damages. Thus, improvements in disk overcoats continue to be of interest.